1. Field of the Invention
The present invention relates to an optical module and a method for aligning the optical module and, more particularly, to a technique related to optical wavelength multiplexing communication.
2. Description of the Related Art
In recent years, WDM (Wavelength Division Multiplexing) of an optical module has been demanded. JP 2013-232514 A discloses an optical module that enables high-density packaging in a small optical transceiver for WDM. A TOSA 30 described in FIG. 6 of JP 2013-232514 A includes a TOSA base 31, four CAN packages 32A to 32D, a plurality of optical components (mirrors, filters, and collimator lenses) set in the TOSA base 31, and a sleeve 33. The mirrors are respectively disposed right under the CAN packages 32A to 32D. Lights pass through the collimator lenses set in optical paths to be changed to parallel lights. The lights are further reflected by the mirrors or the filters and pass the filters according to necessity. The lights (four waves) are combined into wavelength multiplexed light. The wavelength multiplexed light is reflected by the mirrors to change a direction and finally emitted through the sleeve 33.
JP 2010-61139 A discloses an optical module that multiplexes and demultiplexes four-wave multiplexed signals, the optical module increasing an allowable range of alignment accuracy and facilitating aligning work.